(a) A 37 resistor is connected in series with a 7 µF capacitor and a battery. Wh
ID: 1416714 • Letter: #
Question
(a) A 37 resistor is connected in series with a 7 µF capacitor and a battery. What is the maximum charge to which this capacitor can be charged when the battery voltage is 9 V? (When entering units, use micro for the metric system prefix µ.)
(b) Initially the capacitor has zero charge. At what time during the charging process will the charge on this capacitor be 39.8 µC?
I have tried in C MicroC and MicroF neither dimentionally correct
(c) The capacitor is now fully charged. The battery is removed and the capacitor is discharged through a bulb. What will be the charge on the capacitor after 0.259 ms? (Assume that the bulb has the same resistance as the original resistor.)
Explanation / Answer
A.
maximum charge will be after a very long time when capacitor will have total voltage of 9V, then
Q = C*V
Q = 7*10^-6*9 = 63*10^-6 Coulomb
Q = 63 microC
B.
Q = C*V
V= Q/C
V = 39.8*10^-6/(7*10^-6)
V = 5.685 Volt
initially charge = 0
after some time t voltage on the capacitor will be given by
V = Vo*(1 - exp(-t/RC))
rearranging above equation
t = -RC*ln (1 - V/Vo)
t = -37*7*10^-6*ln (1 - 5.685/9)
t = 0.258*10^-3 sec = 0.258 ms
C.
discharging follows this equation
V = Vo*exp (-t/RC)
V = 9*exp(-0.259*10^-3/(37*7*10^-6))
V = 3.31 V
Comment below if you have any doubt.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.